Words by David Richter
Images by Chris Wilson

Without delving too far into sports science, I’ll tell you.


In the summer of 2013, Moxy Monitor launched a new portable monitoring device for the fitness industry. We quickly got our hands on a couple units & began playing around with them.

Previously, to measure fitness & create training zones, we had been using VO2 & lactate testing. I had always questioned some of the variables involved with VO2 & lactate evaluations. But, it was the industry standard, and we made due with what we had at the time. When Moxy came to the industry, I was eager to embrace a new method to study.

I become as educated as possible on Moxy. I played around with the monitors & used them in unison with lactate & VO2. I traveled to seminars & expos where I was usually the only coach in attendance. Most of the audience & all of the presenters were sports scientists.

In 2013, we became Moxy Monitors’ first certified training center. We began hosting seminars & certification of coaches & researchers. Now I’m one of those presenters & Métier recently hosted the Moxy World Summit, where I presented our Wingate protocol.

The Technical Details

Moxy monitors measure SmO₂ & THb.

SmO₂ is short for saturated muscle oxygen. This is the oxygen in your muscle tissue. Oxygen is fuel for your muscles… so we’re measuring aerobic fuel: how much is available, how fast it’s being consumed & how quickly it reloads.

THb is short for total hemoglobin. This metric gives us the total amount of blood in the tissue. THb changes with blood flow.

SmO₂ & THb enables us to pinpoint when your muscles have occlusions: that’s when muscle compression overcomes your blood pressure. These occlusions are an important part of building training zones.

Building Coaching Plans

 I still get excited every time I start talking about what we discover during an evaluation. The four zones we design for training plans are directly related to what we discover during a Moxy evaluation.

The first thing we look for is when supply of SmO2 is more than demand. This is active recovery. Physiological adaptations are minimal in this state, but recovery is optimized. More blood flow to involved muscles equates to faster recovery times compared to simply not exercising.

The next reaction we look for is homeostasis, when supply & demand are equal. This assures a structural training adaptation. Capillary density increases in the involved muscles.

The third & forth zones are marked by occlusions. First a veinous occlusion, then an arterial occlusion.

Locating these reactions yields a clear prescription for training. And when we determine what system is limiting your performance, the workouts can focus on the proper system to focus training.

The Progress of Sports Science

It’s been an enlightening journey as a coach to delve into the science that Moxy monitors provide. It’s flipped sports science on its side & challenged the old methods. It provides us with a ‘power’ meter for your body, not the bike.

Today, as always, we are constantly honing our protocols & beta testing for the best possible evaluations for our athletes.